First off, this is no disrespect to any player of destiny, it's just my opinions. And please read the ENTIRE post before commenting. This goes for PVP and PVE.
Auto rifles in destiny 'pre-nerf' where completely fictional in their performance. No modern rifle could maintain such a high rate of fire and still possess such high stability and damage output. Read or talk to anyone who has served in the military and they will tell you that they focus on using semi auto firing practices to maximize accuracy. Full auto is for Hollywood.
I can hear the rebuttals now, "but it's a future society filled with fictional technology!" Very true, so why then can't The Last Word have the impact stats of a shotgun? Or why can't my Vision of Confluence have the fire rate of a minigun? All I'm saying is that if we want auto rifles to be some sort of 'super AR' then the same freedom must be taken with all other weapon types.
Again, this is just my opinion.